1. Field of the Invention
The present invention relates to an image forming apparatus such as an electrostatic copying machine or an electrostatic printer that uses an electrostatic process, and more particularly to cleaning fiber used in a cleaning apparatuses of the image forming apparatus.
2. Description of the Prior Art
An image forming apparatus such as an electrostatic copying machine or an electrostatic printer of a type using an electrostatic process usually comprises a photosensitive drum having photosensitive layer on the outer surface thereof, the image forming apparatus further comprising, around the photosensitive drum thereof, a charger for uniformly charging the photosensitive member, a developing machine for supplying a charging toner to the photosensitive layer having an electrostatic latent image formed by partial exposure to make the latent image to be a visible image, a transferring unit for transferring the toner on the photosensitive layer onto a transferring member such as paper, an electricity remover unit for removing electricity from the photosensitive layer and the toner after the toner has been transferred, and a cleaning unit for recovering non-transferred toner on the photosensitive layer.
The cleaning unit for the image forming apparatus has been arranged to remove a residual toner by rotating, for example, a fur brush or a nylon brush. Another cleaning unit has been arranged in such a manner that an electric conductive fiber is used to form a brush which electrostatically removes the residual toner.
However, when the fixed toner image is used to form a so-called two-side image by again supplying paper, the conventional structures have suffered from a problem in that a separating agent, such as silicon oil, allowed to adhere to the paper after the image has been fixed is stuck to the paper supply rollers, paper conveyance portion, transferring drum and the photosensitive drum and the like, causing the image forming process to be interrupted. If the silicon oil adheres to the photosensitive drum, a problem called "oil fog" arises.
The mechanism of the generation of the foregoing phenomenon will now be described with reference to FIG. 1.
(1) First, a portion of silicon oil present on the fixed toner image is transferred to the surface of the transferring drum. PA1 (2) Then, the transferred silicon oil present on the transferring drum is shifted to the photosensitive drum through a nip after the rotation has been performed. PA1 (3) The transferred silicon oil brought to the photosensitive drum sticks to the toner present in the vicinity of the photosensitive drum and transfers the toner at the time of the next transferring process, causing the phenomenon called "fog" to take place.
In order to prevent the foregoing phenomenon, the transferred silicon oil must quickly be removed. However, the conventional fur brush cannot remove the silicon oil because it has no function of absorbing the silicon oil.